Two main assumptions of this theory are: people want to overcome equivocality and uncertainty in organizations and a variety of media commonly used in organizations work better for certain tasks than others. Using four criteria, Daft and Lengel present a media richness hierarchy, arranged from high to low degrees of richness, to illustrate the capacity of media types to process ambiguous communication in organizations. The criteria are (a) the availability of instant feedback; (b) the capacity of the medium to transmit multiple cues such as body language, voice tone, and inflection; (c) the use of natural language; and (d) the personal focus of the medium. Face-to-face communication is the richest communication medium in the hierarchy followed by telephone, electronic mail, letter, note, memo, special report, and finally, flier and bulletin. From a strategic management perspective, the media richness theory suggests that effective managers make rational choices matching a particular communication medium to a specific task or objective and to the degree of richness required by that task (Trevino, Daft, & Lengel, 1990, in Soy, 2001).